1) Field of the Invention
The present invention relates to method of turf or lawn (hereifafter collectively called "turf" establishment, and especially to turf-growing methods which can promote uniform germination and good growth of turf over wide areas such as golf courses, playgrounds and horse race tracks. The present invention is also concerned with compsotions of turfgrass seeds and soil suitable for these and other applications.
2) Description of the Related Art
When seeding a large area of ground to establish turf, it is difficult to obtain even distribution of the turfgrass seeds when said seeds are the sole item being distributed. It has heretofore been the practice when seeding the turfgrass seed to mix it with sand soil available at the site or the like, to seed them in the extended state and then to cover them with a covering soil of the same quality as bed soil or top soil. Further, at golf courses and the like, seeded ground surfaces are covered in some instances by cheesecloth, non-woven fabrics or the like with a view toward protecting the seeds from being washed away or otherwise disturbed by wind, rain and/or sprinkled water and also avoiding drying of the top soil layer.
In the method in which turfgrass seeds are mixed with sand or a soil available at the site and then seeded in the extended state, it is however not always easy to achieve uniform mixing of the soil with the turfgrass seeds depending on the grain size distribution and shape of the sand or soil employed as an extender. In some instances, size-dependent separation may take place between turfgrass seeds and soil so that sufficiently uniform seeding may not be carried out. Upon mixing turfgrass seeds with sand or a soil available at the site, it is necessary to apply irksome pretreatment, such as drying, sterilization and elimination of weed seeds, to the sand or soil in advance. Depending on the extender to be employed, problems may arise such that turfgrass seeds would be moved or washed away by watering or rain and also tend to die or scatter away due to drying caused by a delay in work.
On the other hand, the method in which the surface of a seeded ground is covered by cheesecloth, a nonwoven fabric or the like after the seeding also involves problems such that the post-germination control is difficult and, if dissolution and elimination of the cheesecloth, the nonwoven fabric or the like is delayed or the timing of its removal is misjudged, germinated seedlings may be damaged, resulting in poor subsequent growth.